<style>
#loading{
  /*copy from
  http://www.cnblogs.com/wenzheshen/p/5888786.html
  http://simbyone.com/
  */
  height: 100%;
  width: 100%;
  position: absolute;
  z-index: 9999;
  margin-top: 0px;
  top: 0px;
  left: 0px;
  overflow: hidden;
  outline: 0;
  -webkit-overflow-scrolling: touch;
  background-color: rgb(0, 0, 0);
  filter: alpha(opacity=60);
  background-color: rgba(0, 0, 0, 0.6);
  z-index: 9999;

}
#loading-center{
  width: 100%;
  height: 100%;
  position: absolute;
  }
#loading-center-absolute {
  position: absolute;
  left: 50%;
  top: 50%;
  height: 200px;
  width: 200px;
  margin-top: -100px;
  margin-left: -100px;

}
.object{
    -moz-border-radius: 50% 50% 50% 50%;
  -webkit-border-radius: 50% 50% 50% 50%;
  border-radius: 50% 50% 50% 50%;
  position: absolute;
  border-left: 5px solid #FFF;
  border-right: 5px solid #FFF;
  border-top: 5px solid transparent;
  border-bottom: 5px solid transparent;
  -webkit-animation: animate 2s infinite;
  animation: animate 2s infinite;
  }

#object_one{
  left: 75px;
  top: 75px;
  width: 50px;
  height: 50px;
  }

#object_two{
  left: 65px;
  top: 65px;
  width: 70px;
  height: 70px;
  -webkit-animation-delay: 0.1s;
    animation-delay: 0.1s;
  }

#object_three{
  left: 55px;
  top: 55px;
  width: 90px;
  height: 90px;
  -webkit-animation-delay: 0.2s;
    animation-delay: 0.2s;
  }
#object_four{
  left: 45px;
  top: 45px;
  width: 110px;
  height: 110px;
  -webkit-animation-delay: 0.3s;
    animation-delay: 0.3s;

  }

@-webkit-keyframes animate {


50% {
  -ms-transform: rotate(180deg);
    -webkit-transform: rotate(180deg);
    transform: rotate(180deg);
  }

100% {
  -ms-transform: rotate(0deg);
    -webkit-transform: rotate(0deg);
    transform: rotate(0deg);
  }

}

@keyframes animate {

50% {
  -ms-transform: rotate(180deg);
    -webkit-transform: rotate(180deg);
    transform: rotate(180deg);
  }

100% {
  -ms-transform: rotate(0deg);
    -webkit-transform: rotate(0deg);
    transform: rotate(0deg);
  }


}
</style>
<div id="loading" hidden="true">
  <div id="loading-center">
    <div id="loading-center-absolute">
      <div class="object" id="object_four"></div>
      <div class="object" id="object_three"></div>
      <div class="object" id="object_two"></div>
      <div class="object" id="object_one"></div>
    </div>
  </div>
</div>
